GlassScriptPhysician profile
Michael L Chang
NPI 1942543814
$1,371.11
in general payments reported to CMS, 2019-2025
23 companies · none reported in 2025
Payments by year
General payments by program year, as reported to CMS.
General payments by year: 2019: $876 · 2020: $255 · 2021: $130 · 2022: $110.
Who reported paying
General payments only, as reported to CMS. Product names cover 2023-2025.
| Company | General payments | Years | Top products |
|---|---|---|---|
| Pfizer INC. | $160.72 | 2019-2022 | |
| Merck Sharp & Dohme LLC | $152.19 | 2019-2020 | |
| Glaxosmithkline, LLC. | $136.26 | 2019-2020 | |
| Amgen INC. | $131.09 | 2019-2020 | |
| Boehringer Ingelheim Pharmaceuticals, INC. | $117.64 | 2021 | |
| Astrazeneca Pharmaceuticals LP | $96.17 | 2019-2020 | |
| Genzyme Corporation | $74.61 | 2019-2020 | |
| Celgene Corporation | $69.49 | 2019 | |
| Abbvie INC. | $66.65 | 2019-2022 | |
| Horizon Therapeutics Plc | $64.87 | 2019-2020 | |
| Vivus LLC | $41.97 | 2019 | |
| Gilead Sciences, INC. | $36.97 | 2019-2020 | |
| Boston Scientific Corporation | $33.45 | 2019 | |
| Alvogen INC | $25.70 | 2022 | |
| Janssen Biotech, INC. | $25.66 | 2020 |
Show all 23 companies
| Company | General payments | Years | Top products |
|---|---|---|---|
| Janssen Pharmaceuticals, INC | $22.06 | 2019 | |
| Novo Nordisk INC | $21.55 | 2020 | |
| Lilly USA, LLC | $20.37 | 2019 | |
| Ironwood Pharmaceuticals, INC | $18.07 | 2020 | |
| Salix Pharmaceuticals, A Division of Bausch Health US, LLC | $16.49 | 2019 | |
| Takeda Pharmaceuticals U.S.A., INC. | $14.16 | 2019 | |
| Array Biopharma INC | $13.12 | 2022 | |
| Antares Pharma, INC. | $11.85 | 2019 |
If you want to bring it up
Most clinicians are glad to talk about this. A respectful way in:
- "I saw Michael Chang listed in the CMS Open Payments database. Can you tell me about your work with those companies?"
- "Is there a generic or alternative to this medication, and would it work as well for me?"
- "What made you choose this particular treatment for my situation?"
These are normal questions. A good clinician will welcome them.
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Source: CMS Open Payments, program years 2019-2025, as reported to CMS by drug and device makers (published June 30, 2026). Drug and device detail covers 2023-2025.